The present invention concerns an improved speed limiter for lifts provided with catch device.
Passenger lifts and enterable goods lifts are provided with a catch device which by action of a speed limiter is triggered in the event that the normal travelling velocity is exceeded by a given value during downward travel of the cage. Triggering is effected by a rope driving the speed limiter, said rope being attached to the engaging lever of the catch device and running around the rope sheave of the speed limiter, being braked by the latter.
In speed limiters of prior art, in the event of transgression of the operating speed there is by means of rollers or of eccentrically carried cams created a force-induced connection between the driven rope sheave and a stationary cast bell so that triggering of the catch device is initiated by the tension force of the sliding rope over the wedge or seating groove of the rope sheave, now stationary. The tension force acting on the rope is greatly variable. A detrimental feature herein is the jerky stopping of the rope sheave, resulting in looping of the rope and delay of the onset of braking effect.